Low CO2-emissions hybrid solar combined-cycle power system with methane membrane reforming

2008 ◽

Author(s):

Marco Gambini ◽

Michela Vellini

Keyword(s):

Carbon Dioxide ◽

Natural Gas ◽

Co2 Emissions ◽

Power Plants ◽

Fossil Fuels ◽

Combined Cycle ◽

Exhaust Gas ◽

Gas Treatment ◽

Low Co2 ◽

Global Efficiency

In this paper two methodologies, able to avoid CO2 dispersion in atmosphere, have been analyzed: • treating exhaust gases in order to remove, liquefy and store the produced carbon dioxide; • de-carbonizing fossil fuels before using them in the combustion in order to inhibit completely carbon dioxide production. These methodologies have been implemented in advanced power plants based on gas turbine: a combined cycle power plant (CC), fed by natural gas, and an integrated gasification combined cycle (IGCC), fed by coal. The exhaust gas treatment is based on a chemical process of absorption, while the fossil fuel decarbonization is based on partial oxidation of methane, steam methane reforming and coal gasification. These systems require material and energetic integrations with the power sections and so the best interconnections must be investigated in order to obtain good overall performance. With reference to thermodynamic and economic performance, significant comparisons have been made between the above mentioned reference plants. An efficiency decrease and an increase in the cost of electricity have been obtained when power plants are equipped with systems able to reduce CO2 emissions. However, in order to obtain low CO2 emissions when coal is used, the coal decarbonization must be implemented: in this case it is possible to attain a global efficiency of about 38%, a specific emission of 0.1117 kg/kWh and an increase of kWh cost of about 32%. Vice versa, in order to obtain low CO2 emissions when natural gas is used, the exhaust gas treatment must be implemented: in this case it is possible to attain a global efficiency of about 50.7%, a specific emission of 0.0391 kg/kWh and an increase of kWh cost of about 15%. The clean use of coal seems to have good potential because it allows low energy penalizations (about 7.5 percentage points) and economic increases of about 32%. Because of the great availability, the homogeneous distribution and the low cost of this fuel, these results seem to be very interesting especially in the viewpoint of a transition towards the “hydrogen economy”, based, at least in the medium term, on fossil fuels.

Download Full-text

Analysis of Solar-Thermal Power Plants With Thermal Energy Storage and Solar-Hybrid Operation Strategy

Journal of Solar Energy Engineering ◽

10.1115/1.4004246 ◽

2011 ◽

Vol 133 (3) ◽

Cited By ~ 37

Author(s):

Stefano Giuliano ◽

Reiner Buck ◽

Santiago Eguiguren

Keyword(s):

Co2 Emissions ◽

Power Plants ◽

Fossil Fuel ◽

Thermal Power ◽

Combined Cycle ◽

Thermal Power Plants ◽

Hybrid Power ◽

Solar Thermal Power ◽

Low Co2 ◽

Base Load

Selected solar-hybrid power plants for operation in base-load as well as midload were analyzed regarding supply security (dispatchable power due to hybridization with fossil fuel) and low CO2 emissions (due to integration of thermal energy storage). The power plants were modeled with different sizes of solar fields and different storage capacities and analyzed on an annual basis. The results were compared to each other and to a conventional fossil-fired combined cycle in terms of technical, economical, and ecological figures. The results of this study show that in comparison to a conventional fossil-fired combined cycle, the potential to reduce the CO2 emissions is high for solar-thermal power plants operated in base-load, especially with large solar fields and high storage capacities. However, for dispatchable power generation and supply security it is obvious that in any case a certain amount of additional fossil fuel is required. No analyzed solar-hybrid power plant shows at the same time advantages in terms of low CO2 emissions and low levelized electricity cost (LEC). While power plants with solar-hybrid combined cycle (SHCC®, Particle-Tower) show interesting LEC, the power plants with steam turbine (Salt-Tower, Parabolic Trough, CO2-Tower) have low CO2 emissions.

Download Full-text

Sustainability Investigation of Vehicles’ CO2 Emission in Hungary

Sustainability ◽

10.3390/su13158237 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8237

Author(s):

István Árpád ◽

Judit T. Kiss ◽

Gábor Bellér ◽

Dénes Kocsis

Keyword(s):

Energy Efficiency ◽

Co2 Emissions ◽

Energy Supply ◽

Internal Combustion Engines ◽

Combustion Engines ◽

The European Union ◽

New Approach ◽

Technology System ◽

Low Co2

The regulation of vehicular CO2 emissions determines the permissible emissions of vehicles in units of g CO2/km. However, these values only partially provide adequate information because they characterize only the vehicle but not the emission of the associated energy supply technology system. The energy needed for the motion of vehicles is generated in several ways by the energy industry, depending on how the vehicles are driven. These methods of energy generation consist of different series of energy source conversions, where the last technological step is the vehicle itself, and the result is the motion. In addition, sustainability characterization of vehicles cannot be determined by the vehicle’s CO2 emissions alone because it is a more complex notion. The new approach investigates the entire energy technology system associated with the generation of motion, which of course includes the vehicle. The total CO2 emissions and the resulting energy efficiency have been determined. For this, it was necessary to systematize (collect) the energy supply technology lines of the vehicles. The emission results are not given in g CO2/km but in g CO2/J, which is defined in the paper. This new method is complementary to the European Union regulative one, but it allows more complex evaluations of sustainability. The calculations were performed based on Hungarian data. Finally, using the resulting energy efficiency values, the emission results were evaluated by constructing a sustainability matrix similar to the risk matrix. If only the vehicle is investigated, low CO2 emissions can be achieved with vehicles using internal combustion engines. However, taking into consideration present technologies, in terms of sustainability, the spread of electric-only vehicles using renewable energies can result in improvement in the future. This proposal was supported by the combined analysis of the energy-specific CO2 emissions and the energy efficiency of vehicles with different power-driven systems.

Download Full-text

Load-regulation characteristics of gas turbine combined cycle power system controlled with compressor inlet air heating

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2021.117285 ◽

2021 ◽

pp. 117285

Author(s):

Kunle Fan ◽

Cheng Yang ◽

Zhuli Xie ◽

Xiaoqian Ma

Keyword(s):

Power System ◽

Gas Turbine ◽

Combined Cycle ◽

Air Heating ◽

Compressor Inlet ◽

Load Regulation

Download Full-text

Evaluation of Combustion Turbine Systems for the Direct Combustion of Coal

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/85-gt-8 ◽

1985 ◽

Author(s):

Paul A. Berman ◽

Dennis A. Horazak ◽

Paul W. Pillsbury

Keyword(s):

Power Plant ◽

Power System ◽

Operating Cost ◽

Combined Cycle ◽

Coal Conversion ◽

Cost Of Electricity ◽

Direct Combustion ◽

Coal Water Slurry ◽

Plant Site ◽

Baseline System

A combustion turbine combined cycle that uses coal-derived dirty fuels can be economical if the fuel is processed at the plant site and cost of electricity (COE) is used as the criterion for configuring the power system and selecting its components. In a DOE/METC-sponsored study, 12 combinations of power components and conditioning components were evaluated for each of two fuels: a gas made from coal and a coal/water slurry. One baseline system was selected from each group of 12 systems, based on its potential to achieve a low COE. Each baseline system was then parametrically evaluated to show the effects of specific components on the COE of the power plant. In one of these studies, on-site coal conversion was shown as the key to reducing the COE and the operating cost of the plant, thus improving the chances of the plant being used for baseload operation.

Download Full-text